There is often a need to clean dirt from water surfaces of lakes or seas. For example, marine accidents can result in devastating consequences for maritime fauna and flora and can furthermore entail an economic disaster for the fishing and tourist industries in the contaminated areas. The result of a marine accident can in particular be contamination with leaking oil.
The causes of oil contamination of the surfaces of water systems are however not restricted to marine accidents. Oil contamination can also occur as a result of industry in coastal areas, leaking pipelines at the oil transport site itself, natural oil contamination on the sea floor and deliberate oil contamination by ship crews. To remove the oil slicks produced in different ways in the region of the water surface, oil spill response systems, in particular oil spill response vessels, are used. The problem often arises in connection with the process of skimming off the spilled oil that the oil spill response measures must be interrupted owing to the swell. Such interruptions have disadvantageous consequences for the whole oil spill response; the spilled oil can in particular spread over a wider area of the surface of the water system as a thin layer of oil. Furthermore, during swell, the oil slick breaks up into small oil patches which are difficult to locate during the spill response. Furthermore, the oil emulsifies, i.e. it bonds with water and air and as a result becomes more viscous, which makes it much more difficult to remove the oil from the surface of the water system and subsequently separate it on board the oil spill response vessels.
DE 21 21 646 A1 discloses a water craft for responding to oil layers. An opening is provided in the water craft in the region of a bow section, through which opening water contaminated with dirt particles, in particular oil particles, passes into a hold while the water craft navigates over the surface of a water system from which water the dirt particles can be extracted with the aid of a suction device. After passing through the opening in the bow section, the water loaded with dirt particles flows past an edge into the hold.
DE 102 21 069 B4 discloses an apparatus for picking up particles from the surface of a water system in which hydrodynamic separation is used. When skimming off an oil film on a water system, the film flows along a bow underside of the oil pick-up apparatus as far as a separation blade which separates the oil film from the main flow and conducts it into a particle separation chamber, which is also referred to as a moon pool. An eddy is produced at a stall edge of the separation blade, which eddy accelerates the oil to be picked up to the free water surface in the particle separation chamber. The particle-containing water which passes into the particle separation chamber in this manner is prepared further in that the oil particles pass via a ramp out of the particle separation chamber into a particle collection chamber. The particle collection chamber is used for concentrating the separated particles. The particles are pumped from there into storage tanks.
In the known apparatus for picking up particles from the surface of a water system, the separation blade forms a rigid element in the region of the walls of the hull, which is extended for forming the inflow and outflow openings. This process requires considerable application of mechanical force, which makes it necessary to provide corresponding mechanical systems for moving the separation blade. As the known separation blade is not connected structurally to the hull, this reduces the strength of the ship body.